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Floating gate memory (FGM), composed of van der Waals (vdW) junctions with an atomically thin floating layer for charge storage, is widely employed to develop logic-in memories and in-sensor computing devices. Most research efforts of FGM are spent on achieving long-term charge storage and fast reading/writing for flash and random-access memory. However, dynamic modulation of memory time via a tunneling barrier and vdW interfaces, which is critical for synaptic computing and machine vision, is still lacking. Here, a van der Waals short-term memory with tunable memory windows and retention times from milliseconds to thousands of seconds is reported, which is approximately exponentially proportional to the thickness h-BN (hexagonal boron nitride) barrier. The specific h-BN barrier with fruitful gap states provides charge release channels for trapped charges, making the vdW device switchable between positive photoconductance and negative photoconductance with a broadband light from IR to UV range. The dynamic short-term memory with tunable photo response highlights the design strategy of novel vdW memory vis interface engineering for further intelligent information storage and optoelectronic detection.
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Aim: This study was designed to evaluate the contribution of GBAP1 variants to gastric cancer (GC) risk in a Chinese Han population. Methods: The genotypes of GBAP1 polymorphisms were detected using the Agena MassARRAY platform. Logistic regression analysis was used to calculate odds ratios (ORs) and 95% CIs. Results: GBAP1 rs140081212 (OR = 0.51, p = 4.50 × 10-07), rs1057941 (OR = 0.48, p = 1.19 × 10-08) and rs2990220 (OR = 0.46, p = 7.34 × 10-09) contribute to reduced GC risk, especially gastric adenocarcinoma. Interestingly, the contribution of GBAP1 variants to GC susceptibility was associated with age, sex, BMI, smoking and drinking. Conclusion: This research suggested that GBAP1 polymorphisms might provide a protective effect against GC occurrence in a Chinese Han population.
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Neoplasias Gástricas , Estudos de Casos e Controles , China/epidemiologia , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologiaRESUMO
In this paper, the frequency-dependent noise figure of a continuous photonic time-stretch system is theoretically analyzed and experimentally demonstrated. Mathematic analysis discloses that the frequency-dependent noise figure in the continuous photonic time-stretch system is mainly owing to the dispersion-induced phase shift in the link. In the experiment, a completely continuous signal is reconstructed with time-interleaved joining of four sections of time-stretched signals from optical wavelength-division de-multiplexing channels. The result of the frequency-dependent noise figure property agrees well with that of theoretical analysis.
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Photonic time stretch (PTS) has been intensively investigated in recent decades due to its potential application to ultra-wideband analog-to-digital conversion. A high-speed analog signal can be captured by an electronic analog-to-digital converter (ADC) with the help of the PTS technique, which slows down the speed of signal in the photonic domain. Unfortunately, the process of the time stretch is not linear due to the nonlinear modulation of the electro-optic intensity modulator in the PTS system, which means the undesired harmonics distortion. In this paper, we present an exact analytical model to fully characterize the harmonics generation in the PTS systems for the first time, to the best of our knowledge. We obtain concise and closed-form expressions for all harmonics of the PTS system with either a single-arm Mach-Zehnder modulator (MZM) or a push-pull MZM. The presented model can largely simplify the PTS system design and the system parameters estimation, such as system bandwidth, harmonics power, time-bandwidth product, and dynamic range. The correctness of the mathematic model is verified by the numerical and experimental results.
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As one of the most prevalent neurotrophic factors in the central nervous system (CNS), brain-derived neurotrophic factor (BDNF) plays a significant role in CNS injury by binding to its specific receptor Tropomyosin-related kinase receptor B (TrkB). The BDNF/TrkB signaling pathway is crucial for neuronal survival, structural changes, and plasticity. BDNF acts as an axonal growth and extension factor, a pro-survival factor, and a synaptic modulator in the CNS. BDNF also plays an important role in the maintenance and plasticity of neuronal circuits. Several studies have demonstrated the importance of BDNF in the treatment and recovery of neurodegenerative and neurotraumatic disorders. By undertaking in-depth study on the mechanism of BDNF/TrkB function, important novel therapeutic strategies for treating neuropsychiatric disorders have been discovered. In this review, we discuss the expression patterns and mechanisms of the TrkB/BDNF signaling pathway in CNS damage and introduce several intriguing small molecule TrkB receptor agonists produced over the previous several decades.
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Fator Neurotrófico Derivado do Encéfalo , Receptor trkB , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Receptor trkB/metabolismo , Transdução de Sinais , Sistema Nervoso Central/metabolismo , Neurônios/metabolismoRESUMO
Although the pencilfish is a globally popular economic fish in the aquarium market, its taxonomic classification could be further refined. In order to understand the taxonomy of species of the genus Nannostomus (Characiformes, Lebiasinidae) and their phylogenetic position within the order Characiformes, in this study, we characterized mitochondrial genomes (mitogenomes) from four Nannostomus species for the first time. The four mitogenomes exhibited the typical circular structure, with overall sizes varying from 16,661 bp to 16,690 bp. They contained 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and 1 control region (CR). Nucleotide composition analysis suggested that the mitochondrial sequences were biased toward A and T. Bayesian inference and maximum likelihood analyses based on PCGs support the family Lebiasinidae classification, described using four Nannostomus species, clustering together with Lebiasina multimaculata from the same family. The results of this study support the current taxonomic classification of the family Lebiasinidae. Phylogenetic analysis also suggested that gene rearrangement would not significantly impact the phylogenetic relationships within the order Characiformes. These results might provide new data regarding the phylogeny and classification of the order Characiformes, thus providing a theoretical basis for the economic development of aquarium fish markets.
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Sliding ferroelectricity in 2D materials, arising from interlayer sliding-induced interlayer hybridization and charge redistribution at the van der Waals interface, offers a means to manipulate spontaneous polarization at the atomic scale through various methods such as stacking order, interfacial contact, and electric field. However, the practical application of extending 2D sliding ferroelectricity remains challenging due to the contentious mechanisms and the complex device structures required for ferroelectric switching. Here, a sliding memristor based on a graphene/parallel-stacked hexagonal boron nitride/graphene tunneling device, featuring a stable memristive hysteresis induced by interfacial polarizations and barrier height modulations, is presented. As the tunneling current density increases, the memristive window broadens, achieving an on/off ratio of ≈103 and 2 order decrease of the trigger current density, attributed to the interlayer migration of positively charged boron ions and the formation of conductive filaments, as supported by the theoretical calculations. The findings open a path for exploring the sliding memristor via a tunneling device and bridge the gap between sliding ferroelectricity and memory applications.
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Ultrathin 2D ferroelectrics with high Curie temperature are critical for multifunctional ferroelectric devices. However, the ferroelectric spontaneous polarization is consistently broken by the strong thermal fluctuations at high temperature, resulting in the rare discovery of high-temperature ferroelectricity in 2D materials. Here, a chemical vapor deposition method is reported to synthesize 2D CuCrSe2 nanosheets. The crystal structure is confirmed by scanning transmission electron microscopy characterization. The measured ferroelectric phase transition temperature of ultrathin CuCrSe2 is about ≈800 K. Significantly, the switchable ferroelectric polarization is observed in ≈5.2 nm nanosheet. Moreover, the in-plane and out-of-plane ferroelectric response are modulated by different maximum bias voltage. This work provides a new insight into the construction of 2D ferroelectrics with high Curie temperature.
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In recent years, energy efficiency has been considered an extremely cost-effective way to reduce greenhouse gas emissions. China is a country with the world's largest coal consumption and heavy reliance on thermal power generation. Therefore, the relationship between the coal consumption constraint policy (CCCP) in China and electrical energy efficiency is a topic worthy of study. Based on the panel data of 30 provinces in China during 2005-2016, this paper employs the difference-in-differences (DID) to examine the impact of CCCP on electrical energy efficiency in China. The results indicate that the implementation of the CCCP reduces electrical energy efficiency in the pilot provinces. Based on the mechanism tests, the cost effect outweighs the innovation effect, which is why CCCP decreases electrical energy efficiency. The results of the heterogeneity analysis show that the influence of CCCP is more significant in the provinces with weak law enforcement and small hydropower investment and northern provinces. This study suggests that the Chinese government can promote corporate technological innovation by improving the environmental compensation system and increasing environmental law enforcement to improve electrical energy efficiency. Meanwhile, renewable energy projects should be the focus of future investment. Supplementary Information: The online version contains supplementary material available at 10.1007/s12053-022-10023-2.
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The stomach is the main digestive organ in humans. Patients with gastric cancer often develop digestive problems, which result in poor nutrition. Nutritional status is closely related to postoperative complications and quality of life (QoL) in patients with gastric cancer. The controlling nutritional status (CONUT) score is a novel tool to evaluate the nutritional status of patients. However, the relationship of the CONUT score with postoperative complications, QoL, and psychological status in patients with gastric cancer has not been investigated. The present follow-up study was conducted in 106 patients who underwent radical gastrectomy in our hospital between 2014 and 2019. The CONUT score, postoperative complications, psychological status, postoperative QoL scores, and overall survival (OS) of patients with gastric cancer were collected, and the relationship between them was analyzed. A significant correlation was observed between the CONUT score and postoperative complications of gastric cancer (P < 0.001), especially anastomotic leakage (P = 0.037). The multivariate regression analysis exhibited that the CONUT score (P = 0.002) is an independent risk factor for postoperative complications. The CONUT score was correlated with the state anxiety questionnaire (S-AI) for evaluating psychological status (P = 0.032). However, further regression analysis exhibited that the CONUT score was not an independent risk factor for psychological status. Additionally, the CONUT score was associated with postoperative QoL. The multivariate regression analysis exhibited that the CONUT score was an independent risk factor for the global QoL (P = 0.048). Moreover, the efficiency of CONUT score, prognostic nutrition index, and serum albumin in evaluating complications, psychological status, and QoL was compared, and CONUT score was found to outperform the other measures (Area Under Curve, AUC = 0.7368). Furthermore, patients with high CONUT scores exhibited shorter OS than patients with low CONUT scores (P = 0.005). Additionally, the postoperative complications (HR 0.43, 95% CI 0.21-0.92, P = 0.028), pathological stage (HR 2.26, 95% CI 1.26-4.06, P = 0.006), and global QoL (HR 15.24, 95% CI 3.22-72.06, P = 0.001) were associated with OS. The CONUT score can be used to assess the nutritional status of patients undergoing gastric cancer surgery and is associated with the incidence of postoperative complications and QoL.
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Gastrectomia , Desnutrição/diagnóstico , Avaliação Nutricional , Estado Nutricional , Neoplasias Gástricas/cirurgia , Fístula Anastomótica/etiologia , Biomarcadores/sangue , Colesterol/sangue , Feminino , Gastrectomia/efeitos adversos , Gastrectomia/mortalidade , Humanos , Contagem de Linfócitos , Masculino , Desnutrição/etiologia , Desnutrição/mortalidade , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Qualidade de Vida , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Albumina Sérica Humana/análise , Neoplasias Gástricas/complicações , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Dapagliflozin, a sodium glucose transporter protein-2 (SGLT-2) inhibitor, reduces the risk for cardiovascular diseases. However, the influence of dapagliflozin on nondissecting abdominal aortic aneurysms (AAAs) remains unclear. METHODS: AAAs were created in male C57BL/6 mice via intra-aortic porcine pancreatic elastase (PPE) infusion. Mice were daily treated with dapagliflozin (1 or 5 mg/kg body weight) or an equal volume of vehicle through oral gavage beginning one day prior to PPE infusion for 14 days. To investigate its translational value, dapagliflozin or vehicle was also administered to mice with existing AAAs in another cohort. Aortic diameters were measured prior to (day 0 for baseline) and 14 days after PPE infusion. After sacrifice, mice aortae were collected, and following histological analyses were performed. RESULTS: Dapagliflozin treatment significantly reduced aneurysmal aortic expansion following PPE infusion as compared to vehicle treatment especially at 5 mg/kg body weight (approximately 21% and 33% decreases in 1 and 5 mg/kg treatment groups, respectively). The dose-dependent attenuation of AAAs by dapagliflozin was also confirmed on histological analyses. Dapagliflozin remarkably reduced aortic accumulation of macrophages, CD4+ T cells, and B cells particularly following dapagliflozin treatment at 5 mg/kg. Dapagliflozin treatment also markedly attenuated medial SMC loss. Though the difference was not significant, dapagliflozin treatment tended to attenuate CD8+ T cells and elastin degradation. Dapagliflozin treatment at 5 mg/kg caused a 53% reduction in neovessel density. Furthermore, dapagliflozin treatment mitigated further progress of existing AAAs. CONCLUSION: Dapagliflozin treatment ameliorated PPE-induced AAAs by inhibiting aortic leukocytes infiltration and angiogenesis.
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Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/tratamento farmacológico , Aortite/complicações , Aortite/tratamento farmacológico , Compostos Benzidrílicos/administração & dosagem , Progressão da Doença , Glucosídeos/administração & dosagem , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Animais , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/imunologia , Aortite/imunologia , Aortite/patologia , Linfócitos B/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/tratamento farmacológico , Elastase Pancreática/efeitos adversos , Suínos , Resultado do TratamentoRESUMO
BACKGROUND: Porcine pancreatic elastase (PPE) is successfully used to induce abdominal aortic aneurysm (AAA) in mice. However, differences between mouse strains in susceptibility to PPE induction have been reported. Kunming mouse is one of the most frequently used strains in China but whether it is suitable for induction of AAA by PPE application remains unclear. METHODS: PPE infusion (1.5 units/ml) in temporary controlled aorta was performed to induce AAAs in both C57BL/6J and Kunming mice. Phosphate-buffered saline (PBS) application was used as vehicle control. The aorta diameters of all mice were measured at days 0 and 14 after surgery to evaluate the AAA formation. RESULTS: After 14 days of PPE or PBS infusion, all mice were sacrificed and aorta tissues were collected for histological staining analysis. At the 14th day after infusion, PPE successfully induced aortic dilation in Kunming mice and typical AAA in C57BL/6J mice. The aorta diameter increased by 0.23 mm in Kunming mice after PPE infusion, while it was 0.72 mm in the C57BL/6J strain. PPE induced mild elastin degradation, smooth muscle cell (SMC) depletion and mural leucocyte infiltration in Kunming mice, but in PPE-sensitive C57BL/6J mice, it induced total loss of SMCs, elastin disappearance and diffused infiltrated leucocytes in aortic aneurysmal segments. The effects of PPE in inducing angiogenesis and upregulating matrix metalloproteinase 2 and 9 expression in Kunming mice were also weaker than that in C57BL/6J mice. CONCLUSION: At the reported dose of PPE, Kunming mouse is not as susceptible to AAA formation as C57BL/6J mice. The failure of PPE to induce AAA formation in Kunming mice may be associated to its inability to boost a strong inflammatory response.
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Aneurisma da Aorta Abdominal , Elastase Pancreática , Animais , Aorta Abdominal , Aneurisma da Aorta Abdominal/induzido quimicamente , Modelos Animais de Doenças , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Elastase Pancreática/efeitos adversos , SuínosRESUMO
Neural electrodes are used for acquiring neuron signals in brain-machine interfaces, and they are crucial for next-generation neuron engineering and related medical applications. Thus, developing flexible, stable and high-resolution neural electrodes will play an important role in stimulation, acquisition, recording and analysis of signals. Compared with traditional metallic electrodes, electrodes based on graphene and other two-dimensional materials have attracted wide attention in electrophysiological recording and stimulation due to their excellent physical properties such as unique flexibility, low resistance, and high optical transparency. In this review, we have reviewed the recent progress of electrodes based on graphene, graphene/polymer compounds and graphene-related materials for neuron signal recording, stimulation, and related optical signal coupling technology, which provides an outlook on the role of electrodes in the nanotechnology-neuron interface as well as medical diagnosis.
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Interfaces Cérebro-Computador , Grafite , Animais , Encéfalo/fisiologia , Eletrodos , HumanosRESUMO
OBJECTIVE: Elastase-induced abdominal aortic aneurysm (AAA) model is widely used for aneurysmal pathogenesis and translational research. However, temporal alternations in aneurysmal histologies remain unknown. This study is aimed at analyzing temporal immunopathologies of aneurysmal aorta following experimental AAA induction. METHODS: Male C57BL/6J mice at the age of 10-14 weeks received intra-aortic infusion of elastase to induce AAAs. Aortic diameters at the baseline and indicated days after AAA induction were measured, and aortae were collected for histopathological analysis. RESULTS: Aorta diameters increased from 0.52 mm at the baseline levels to 0.99 mm, 1.34 mm, and 1.41 mm at days 7, 14, and 28, respectively, corresponding 90%, 158%, and 171% increases over the baseline level. Average aortic diameters did not differ between days 14 and 28. Severe elastin degradation and smooth muscle cell depletion were found at days 14 and 28 as compared to the baseline and day 7. No difference in the scores of medial elastin and SMC destruction was noted between days 14 and 28. Consistent results were found for leukocyte accumulation, neoangiogenesis, and matrix metalloproteinase expression. Twenty-eight days after AAA induction, all aneurysmal pathologies showed an attenuated trend, although most histopathological parameters did no differ between days 14 and 28. CONCLUSION: Our data suggest that almost aneurysmal immunohistopathologies reach maximal 14 days following AAA induction. Analysis of day 14 histologies is sufficient for AAA pathogenesis and translational studies in elastase-induced mouse experimental AAAs.
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Aorta/patologia , Aneurisma da Aorta Abdominal/imunologia , Miócitos de Músculo Liso/patologia , Animais , Aorta/metabolismo , Aneurisma da Aorta Abdominal/patologia , Modelos Animais de Doenças , Elastina/metabolismo , Humanos , Infusões Intra-Arteriais , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica , Elastase Pancreática/metabolismoRESUMO
BACKGROUND/AIMS: There has been debate on whether a sodium-restricted diet (SRD) should be used in cirrhotic patients with ascites in China in recent years. The purpose of this study was to compare the effect of sodium-restricted and unrestricted diets on plasma renin activity (PRA), renal blood flow (RBF) and ascites in patients with liver cirrhosis. METHODS: Two hundred cirrhotic patients with ascites were randomly divided into two groups (98 cases in the sodium-unrestricted diet [SUD] group and 102 cases in the SRD group); 95 patients (96.94%) in the SUD group and 97 patients (95.1%) in the SRD group had post-hepatitis B cirrhosis. RESULTS: Blood sodium and RBF were higher in SUD group than in SRD group (p<0.001), while PRA were significantly lower in SUD group than the SRD group 10 days after treatment (p<0.001). Renal impairment caused by low blood sodium was higher in SRD group than in SUD group (p<0.01). Ascites disappeared in higher proportion of patients in SUD group than in SRD group (p<0.001). CONCLUSIONS: SUD can increase the level of blood sodium and RBF, and be beneficial to diuresis and ascite reduction and disappearance.